Why join?

It comes ahead of the G20 summit in China on 4-5 September, where German chancellor Angela Merkel and French president Francois Hollande will also meet Putin about the situation in Ukraine and the implementation of the so-called Minsk ceasefire agreement.

It also come before EU member states start a discussion on EU-Russia relations and the bloc's sanctions on Russia.

EU sanctions on Russia are due to be a topic of a planned meeting of EU leaders in October, where they will be discussed within the context of a wider discussion on the bloc’s Russia policy.

A first discussion will be held at an informal meeting of foreign ministers in Bratislava next week.

Slovakia currently chairs the EU Council presidency, giving Fico some leeway to shape the EU agenda.

The Slovak prime minister has in the past been a fierce critic of the sanctions, which were put in place after Russia annexed Ukraine’s Crimea in 2014. They are renewed every six months, but critics - including Fico - say they have failed to yield any results. Fico considers Russia an important economic partner, particularly in the field of energy.

The other meetings

On Thursday morning, before flying to Russia, Fico will have a bilateral meeting with French president Francois Hollande in Paris. On Friday, he will meet Merkel and leaders of the other Visegrad group countries (Czech Republic, Hungary and Poland) in Warsaw.

Lest week Merkel defended the measures, saying they should be prolonged as Russia has not lived up to its commitments under the Minsk agreement.

In an interview with RedaktionsNetzwerks Deutschland she said that Russia had caused a huge crisis by its actions in Ukraine.

"Europe had to react against this violation of basic principles," Merkel said. "This [the accord] is and remains the yardstick for the future of the sanctions.”

She added that she was working with Hollande "with all one's strength" to urge Ukraine and Russia to abide by the Minsk deal.

The Franco-German duo spoke on the phone with Putin on Tuesday (23 August), the Kremlin told Reuters, adding that Putin had shared his concerns over Ukrainian "provocations" with his counterparts.